This proposal describes a peptide-oligonucleotide synthesis facility for shared use by 22 co-principal investigators and other members of the UCSD biomedical community. The core group of 22 co-PI's all hold active NIH grants and will account for more than 75 percent of the usage. Five other participants either have NIH grant applications pending or are funded from other federal sources. The co-PI's are from the Departments of Chemistry (4), Biology (4), Medicine (8), Pathology (2), Reproductive Medicine (2), Pediatrics (1) and Marine Biology (1). The application requests an ensemble of equipment for the automatic synthesis and characterization of peptides and oligonucleotides. Peptides will be used in a wide variety of experiments in three areas: (a) synthetic peptides for immunochemical identification and isolation of putative proteins, (b) biologically active peptides and (c) peptide substrates. The first group includes studies on viral proteins (murine hepatitis, polio, etc.), cell-cycle regulators in yeast, minor fibrinogen variants, preprohormones, variant cAMP-dependent protein knases, and other proteins known only through their DNA sequences. The second group (biologically active peptides) includes studies on various releasing factors, thymus-derived peptides, peptides thought to induce celiac disease, and peptides involved in fertilization phenomena. The last group (chromogenic substrates) includes studies in the area of blood coagulation, especially factor IX. Oligonucleotides will be used by no fewer than 13 of the 22 co-PI's, mainly for primers in cloning studies, but also as probes for locating and identifying genes. One project involves site-directed mutagenesis in conjunction with the known X-ray structures of proteins.